676
ACUS48 KWNS 240900
SWOD48
SPC AC 240859

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0359 AM CDT Mon Aug 24 2026

Valid 271200Z - 011200Z

...DISCUSSION...
A strong mid-level ridge will be centered over the Rockies on
Thursday with a broad trough centered across the Great Lakes. The
ridge will break down over the weekend with a more zonal flow with
embedded shortwave troughs extending from the Northwest to the
northern Plains and into the Northeast. Beyond this weekend,
guidance differs on the evolution of the pattern with considerable
uncertainty.

...D7/Sunday to D8/Monday - Northern Plains...
Guidance continues to consolidate around an unseasonably strong
mid-level shortwave trough across the northern Plains into the Upper
Midwest on Sunday and Monday. There is still some spread around the
timing of this trough and also the degree of destabilization ahead
of it. However, despite these timing differences, a moderately
strong signal for an increasing severe weather threat in this period
appears to be emerging as a trough with a consistent convective
signal is shown by the ECMWF and GFS and also by the AI-GFS and
AI-ECMWF. Ensemble guidance shows a flattened ridge with a mid-level
jet streak across this region during the same timeframe.
Surprisingly, AI/ML guidance shows very little signal for a severe
threat across this region. Analysis of individual ensemble members
suggests this is likely reflective of the uncertainty in timing and
location of this trough and greater spread among the ensemble
guidance. Nonetheless, the potential for an organized severe weather
threat across the northern Plains and/or Upper Midwest late this
weekend into early next week appears to be increasing. If guidance
continues to consolidate with decreasing spread about the timing of
the trough, severe weather probabilities may eventually be needed.

..Bentley.. 08/24/2026